[Correlation between dyslipidemia and the risk of papillary thyroid carcinoma].

Objective: To investigate the correlation between dyslipidemia and the risk of papillary thyroid carcinoma (PTC). Methods: A case-control study was conducted. PTC patients diagnosed by pathology in Tianjin Medical University Cancer Institute and Hospital from April 2014 to August 2019 were enrolled as the experimental group, and healthy controls in the physical examination center at the same time were also enrolled as the control group. The demographic data and blood lipid parameters of the subjects were collected. Multivariate logistic analyses were used to assess the correlation between dyslipidemia and the risk of PTC. Results: A total of 2 000 cases of PTC were enrolled, with a mean age of (42±12) years, including 1 419 females (71.0%) and 581 males (29.0%). There were 4 524 cases in the control group, with a mean age of (42±9) years, including 3 311 females (73.2%) and 1 213 males (26.8%). There was no statistically difference in age and gender between the two groups (both P>0.05). Compared with the control group, triglyceride (TG) [(1.7±1.1) vs (1.4±1.0) mmol/L, P<0.001] and low-density lipoprotein (LDL) [(2.9±0.8) vs (2.8±0.7) mmol/L, P=0.015] increased in peripheral blood of PTC patients, while high-density lipoprotein (HDL) [(1.3±0.4) vs (1.4±0.3) mmol/L, P<0.001] decreased, but the difference was not statistically significant in total cholesterol (TC) [(4.9±1.0) vs (4.9±0.8) mmol/L, P=0.172]. After adjusting for age and gender, increase of TC (OR=1.20, 95%CI: 1.06-1.34, P=0.003), TG (OR=1.73, 95%CI: 1.55-1.94, P<0.001), LDL (OR=1.21, 95%CI: 1.08-1.36, P=0.001), LDL/HDL (OR=1.77, 95%CI: 1.56-2.02, P<0.001) and decrease of HDL (OR=3.15, 95%CI: 2.78-3.58, P<0.001) were the related factors of PTC. Conclusions: Compared with the control group, patients with PTC have higher level of TG and LDL and lower level of HDL. Dyslipidemia is an important factor related to the risk of PTC.

[Epidemiological investigation on allergic diseases related to animal dander of cats, dogs and horses].

Objective: A multicenter Chinese mainland survey was conducted to investigate the sensitization distribution characteristics of cat, dog and horse dander in patients with allergic diseases, so as to provide clinicians with epidemiological data of common animal allergens and useful information for the prevention and treatment of allergies in cats, dogs and horses. Methods: The epidemiological investigation and design was adopted. This study is based on the national epidemiological survey of allergic diseases led by the first affiliated Hospital of Guangzhou Medical University. From January to December in 2021, a total of 2 122 patients diagnosed with allergic diseases were included in the outpatient department of respiratory department/pediatrics/allergy department of 14 units such as the First Affiliated Hospital of Guangzhou Medical University, and 222 healthy subjects were included as controls from the physical examination center of the above units in the same period. All the subjects filled out the allergic disease questionnaire under the guidance of doctors, and the allergen-specific immunoglobulin E (sIgE) of cats, dogs and horses of all subjects were detected by magnetic particle chemiluminescence system. The epidemiological characteristics of three animal allergens in different diseases, ages and regions were analyzed. Chi square test was used to analyze the frequency difference between groups, t test or Mann Whitney U test was used to test the distribution difference between two groups, and one-way ANOVA or Kruskal Wallis H test was used to compare the distribution difference between multiple groups. Bar chart, Venn-plot and radar chart were drawn to show the sensitization distribution characteristics. A small number of missing values caused by subjects' omission have been excluded during the analysis. Results: The 2 122 patients with allergic diseases were 57.35% male (1 217/2 122) and 40.95% female (869/2 122), and 1.70% (36/2 122) patients had loss of gender information. The age of patients with allergic diseases was 9.0 (6.0, 28.0) years, while that of healthy controls was 29.0 (13.0, 39.0) years old, and there were 1.7% (36/2 122) and 0.9% (2/222) subjects with missing age information, respectively. The proportion of caesarean section in allergic patients was significantly higher than that in healthy controls (31.4% vs. 17.6%,χ2=16.582,P<0.001) [2.5% (54/2 122) of the patient group and 5.4% (12/222) of the control group had missing birth mode information], and the proportion of patients with allergic diseases who reported that both parents had allergic diseases was significantly higher than that of the control group (35.7% vs. 9.5%, χ2=65.171,P<0.001). Patients with allergic diseases are mainly school-age (6-12 years old) and adolescents (12-18 years old). 16.4% of patients with allergic diseases were sensitized to cat dander, 10% and 6% to dog and horse dander. The sensitization rate of cat dander in patients with rhinitis, asthma, conjunctivitis, food allergy and atopic dermatitis was the highest (16.4%-21.6%), followed by dog dander (10.2%-15.2%). The prevalence of allergic rhinitis was the highest among different animal sensitized populations. The proportion of cat, dog and horse allergens sensitized at the same time is between 10%-15%, and the proportion of any two or more animal dander sensitized at the same time is about 45%. Animal allergens are associated with respiratory allergic diseases, especially allergic rhinitis with allergic conjunctivitis. There were significant differences in the distribution of positive rates of three animal allergens in different regions, and the highest positive rate of cat dander was found in all provinces of the country. Conclusion: The sensitization rate of animal dander allergens increased significantly, and the highest was in children and adolescents. Cat dander is the most common animal allergen, followed by dog. Different animals show obvious cross or common sensitization due to their high homology.

[Analysis of serum allergen-specific IgE in children with respiratory allergic disease in Guangdong].

Objective: To investigate the common allergens in children with respiratory allergic diseases in Guangdong and provide the basis for preventing and treating respiratory allergic diseases. Methods: A total of 254 serum samples were collected retrospectively from children with allergic rhinitis and (or) asthma in the pediatric clinic of the First Affiliated Hospital of Guangzhou Medical University or Boai Hospital of Zhongshan City from August 2019 to August 2020 and tested positive for at least one allergens by ImmunoCAP 1000 or skin prick test. There were 173 males and 81 females, with a median age (interquartile interval) of 7 (4.00, 9.75) years. Specific IgE against eighteen common allergen were tested by magnetic particle chemiluminescence immunoassay. Statistical analysis using χ2 test. Results: The positive rate of Dermatophagoides pteronyssinus (85.0%, 215/254) was the highest, followed by D. farinae (83.5%, 212/254), egg white (19.3%, 49/254), milk (14.6%, 37/254), German cockroach (14.2%, 36/254) and ox-eye daisy (12.6%, 32/254). Dust mites were the most common allergens in patients with allergic rhinitis / allergic asthma / allergic rhinitis and asthma. The positive rates of D. pteronyssinus (95.4% vs. 91.7% vs. 71.0%, χ2=23.257, P<0.001), D. farinae (95.4% vs. 90.6% vs. 67.7%, χ2=26.916, P<0.001), mugwort (10.8% vs. 9.4% vs. 1.1%, χ2=7.535, P=0.023), and ox-eye daisy (21.5% vs. 14.6% vs. 4.3%, χ2=10.876, P=0.004) in allergic rhinitis combined with asthma group and allergic rhinitis group were significantly higher than those in allergic rhinitis group. The positive rates of D. pteronyssinus (96.2% vs. 84.0% vs. 53.5%, χ2=46.343, P<0.001), D. farinae (96.2% vs. 81.5% vs. 48.8%, χ2=52.756, P<0.001) and German cockroach (17.7% vs. 14.8% vs. 2.3%, χ2=6.313, P=0.043) in > 6 years old group were significantly higher than those in > 3 years old group and > 3-6 years old group, while the sIgE positive rates of egg white (41.9% vs. 21.0% vs. 10.8%, χ2=20.281, P<0.001) and milk (41.9% vs. 16.0% vs. 4.6%, χ2=36.227, P<0.001) in ≤3 years old group were significantly higher than those in > 3-6 years old group and > 6 years old group. In addition, there were significant positive correlations between D. pteronyssinus and D. farinae, mugwort and ox-eye daisy, cat dander and horse dander, ox-eye daisy and dandelion, egg white and milk, timothy grass and sesame (rs≥0.511, P < 0.01). With the increase of the class of house dust mite allergen, the sIgE positive rates of mugwort (0.0% vs. 1.5% vs. 10.8%, χ2=9.714, P=0.008), ox-eye daisy (0.0% vs. 4.4% vs. 19.6%, χ2=16.195, P<0.001), cat dander (0.0% vs. 7.4% vs. 18.2%, χ2=11.459, P=0.003) and horse dander (0.0% vs. 1.5% vs. 15.5%, χ2=15.443, P < 0.001) increased significantly, while the sIgE positive rate of milk (29.0% vs. 16.2% vs. 10.1%, χ2=8.792, P=0.012) decreased significantly. Conclusions: Dust mite is the main allergen in children with respiratory allergic diseases in Guangdong, and ox-eye daisy is the main pollen allergen. The sensitization patterns of allergens varied in different ages and diseases, and children with respiratory allergic diseases should regularly detect allergens and pay attention to avoid them.

NLRP6 suppresses the inflammatory response of human periodontal ligament cells by inhibiting NF-κB and ERK signal pathways.

AIM: To explore the function and mechanisms of NLRP6 (NOD-, LRR- and pyrin domain-containing 6) in the inflammatory response of human periodontal ligament cells (HPDLCs). METHODOLOGY: Tissues associated with apical periodontitis were obtained from three patients who underwent endodontic microsurgery. The expression of NLRP6 in 3 human apical periodontitis tissues and HPDLCs was examined by immunohistochemistry and immunofluorescence, respectively. The expressions of NLRP6, Phospho(p)- p65, p65, IκB-α, p- IκB-α, ERK, p- ERK, NLRP3, Pro interleukin (IL)-1ß, Pro caspase-1 and apoptosis-associated speck-like protein containing a CARD (ASC) were examined by western blot. The gene expression and secretion of proinflammatory cytokines were detected using quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Data were analysed statistically with independent sample t-tests. RESULTS: NLRP6 was expressed in inflammatory periapical tissues and HPDLCs. Lipopolysaccharide (LPS) from Escherichia coli induced NLRP6 in HPDLCs (P < 0.05). After silencing NLRP6, E. coli LPS-induced activation of NF-κB and ERK signalling was enhanced, which was also accompanied by elevated levels of IL-6 and tumour necrosis factor-α (TNF-α) (P < 0.05). Moreover, knockdown of NLRP6 led to up-regulation of NLRP3, Pro IL-1ß and Pro caspase-1 (P < 0.05), whereas down-regulation of ASC (P < 0.05), which may contribute to unchanged levels of IL-1ß in HPDLCs inflammation. CONCLUSION: NLRP6 was functionally expressed in inflamed periapical tissues and HPDLCs. NLRP6 negatively regulated the production of IL-6 and TNF-α in HPDLCs inflammation by inhibiting NF-κB and ERK signal pathways.

NLRP3 inflammasome may regulate inflammatory response of human periodontal ligament fibroblasts in an apoptosis-associated speck-like protein containing a CARD (ASC)-dependent manner.

AIM: To explore the role of NLRP3 (NACHT [nucleotide-binding oligomerization], LRR [leucine-rich repeat] and PYD [pyrin domain] domains-containing protein 3) inflammasome in the inflammatory response of human periodontal ligament fibroblasts (HPDLFs). METHODOLOGY: The expression of NLRP3 and apoptosis-associated speck-like protein containing a CARD (ASC) in inflammatory periapical tissues and HPDLFs was examined by immunohistochemical and immunofluorescent staining. HPDLFs were stimulated with muramyl dipeptide (MDP) and lipopolysaccharide (LPS) from E. coli with or without the silencing of ASC. The expression of NLRP3, ASC and caspase-1 was examined using quantitative real-time polymerase chain reaction. The secretion of proinflammatory cytokines, including interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) was measured in the cell supernatant with an enzyme-linked immunosorbent assay. Data were statistically analysed using independent sample t-tests. RESULTS: Immunohistochemistry and immunocytochemistry staining revealed that NLRP3 and ASC were expressed in HPDLFs and inflammatory periapical tissues. MDP and LPS promoted the expression of NLRP3, ASC and caspase-1 in HPDLFs (P < 0.05). The secretion of proinflammatory cytokines was also increased with MDP and LPS stimulation (P < 0.05). After silencing ASC, the secretion of IL-1ß induced by MDP and LPS was significantly attenuated (P < 0.05). CONCLUSION: In HPDLFs, MDP and LPS activated NLRP3 inflammasome and induced IL-1ß secretion. ASC plays an important role in this inflammatory response.

Apically extruded debris and irrigant with two Ni-Ti systems and hand files when removing root fillings: a laboratory study.

AIM: To compare the amount of apically extruded debris and irrigant produced by two Ni-Ti instruments and hand files when removing root fillings, and to compare two experimental models. METHODOLOGY: Sixty single straight root canals in human mandibular premolars were prepared with K-files and filled with gutta-percha and AH Plus sealer. The teeth were randomly divided into three groups of 20 for removal of the root filling material with Reciproc files (Group 1, RP), Mtwo retreatment files (Group 2, MR) or hand files (Group 3, H). Each group was then equally divided into experimental subgroups: A, with 1.5% agar gel model (AG); B, with empty tube model (ET). Apically extruded debris and irrigant was quantified by subtracting the initial weight of the test apparatus without a tooth from its weight after the root canal retreatment. Comparative analysis of the amount of apically extruded debris and irrigant for each of the instruments and the experimental models was performed. Time for gutta-percha removal was recorded. Data were statistically analysed using one-way analysis of variance. RESULTS: Removal of root fillings with two Ni-Ti instruments produced less apically extruded debris and irrigant than hand files in both experimental models (P < 0.05). More apically extruded debris and irrigant was produced with Reciproc files than Mtwo retreatment files using the 1.5% agar gel model (P > 0.05). Significantly more apically extruded debris and irrigant was produced with Reciproc files than Mtwo retreatment files using the empty tube model (P < 0.05). The time required to remove the root fillings followed Reciproc

[Effect of straight-line minimally invasive access cavity on the mechanical properties of maxillary first premolars: a finite element analysis].

Objective: To investigate the effects of straight-line minimally invasive access cavity on the mechanical properties of endodontically treated maxillary first premolars using finite element analysis. Methods: Micro-CT data of twenty maxillary first premolars were collected for three-dimensional reconstruction. Three access cavities, including the conventional access cavity (ConvAC), the truss access cavity (TrussAC) and the straight-line minimally invasive access cavity (SMIAC), as well as the root canal treatment procedure, were simulated in all the 20 reconstruction samples of three-dimensional models, respectively. The peak von Mises stress on the cervical area of each model, as well as the stress distribution under vertical and oblique loading circumstances, were subsequently determined by using finite element analysis. Results: In comparison to the stresses of ConvAC [buccal cervical (BC): (188.7±13.4) MPa, palatal cervical (PC): (200.9±25.7) MPa], the stresses of TrussAC [BC: (146.0±12.9) MPa, PC: (167.6±15.9) MPa] (t=9.01, P<0.001; t=4.59, P<0.001) and SMIAC [BC: (142.6±13.7) MPa, PC: (168.1±17.4) MPa] (t=9.64, P<0.001; t=3.76, P=0.004) significantly reduced the peak von Mises stress on the cervical area of the maxillary first premolars after root canal treatment. Under vertical loading conditions, SMIAC also reduced the central tendency of stresses on the occlusal surface, cervical area and root. In the case of oblique loading conditions, similar results were observed. Under both loading conditions, there was no significant difference in the peak von Mises stress on the cervical area of the maxillary first premolar between TrussAC and SMIAC groups. Conclusions: The design of SMIAC could preserve the mechanical properties of the maxillary first premolar following root canal treatment, which might have certain clinical feasibility.

[Correlations of serum TgAb and TPOAb and clinicopathological features of PTC in children and adolescents].

Objective: To analyze the correlations between serum thyroglobulin antibody (TgAb) and thyroid peroxidase antibody (TPOAb) and clinicopathological features in children and adolescents with papillary thyroid carcinoma (PTC). Methods: A retrospective analysis was conduced on the clinicopathological data of children and adolescents (age≤21 years old) with PTC admitted to Tianjin Medical University Cancer Hospital from 2011 to 2019, and then, we used χ2 test or Fisher's exact probability test to compare the differences in clinicopathological characteristics between groups with different TgAb and TPOAb status and multivariate logistic regression model analysis to evaluate independent predictors of cervical lymph node metastasis. Results: A total of 304 patients, including 89 males and 215 females, aged 5-21 years (median age 19 years), were enrolled in this study. The comparison between groups with different TgAb and TPOAb status showed that there were significant differences in gender, preoperative thyroglobulin (Tg) level, primary tumor location, number of primary tumors and maximum tumor diameter (all P<0.05), which suggested that TgAb+group (n=81) and TPOAb+group (n=84) had relatively better primary tumor characteristics. Patitents with TgAb+and TPOAb+were more common in females and their preoperative Tg level was mostly within the normal range, and there were significant differences in primary tumor location, number of primary tumors and maximum tumor diameter between TgAb+and TgAb-(223 cases) groups (all P<0.05). There was significant difference in the maximum tumor diameter between TPOAb+and TPOAb-(220 cases) groups (P<0.05). Analysis of risk factors for cervical lymph node metastasis showed that independent risk factors for central lymph node metastasis were maximum tumor diameter>2 cm (OR=2.84, 95%CI: 1.59-5.07, P<0.001) and extra-thyroid extension (OR=0.32, 95%CI: 0.17-0.60, P<0.001), and independent risk factors for lateral neck lymph node metastasis included age≤14 years old (OR=0.34, 95%CI: 0.18-0.67, P=0.002), preoperative Tg+(OR=2.16, 95%CI: 1.10-4.24, P=0.026) and maximum tumor diameter>2 cm (OR=3.99, 95%CI: 2.33-6.82, P<0.001). Conclusion: It is recommended to test routinely serum TgAb and TPOAb before surgery in children and adolescents with PTC. Preoperative Tg+, age≤14 years, maximum tumor diameter>2 cm, and extra-thyroid extension are risk factors for cervical lymph node metastasis.

[Clinical management and prognosis evaluation of pulp regeneration therapy].

Pulp regeneration in a tooth with pulp necrosis is the research hotspot in current clinical treatment of endodontic diseases. Up to now, the revascularization therapy, which is one of the regenerative endodontic treatment, and the most extensive and effective method in clinical practice, can partially achieve the goal of pulp regeneration and root development in young permanent immature teeth. In order to standardize the technique and improve the curative effect, this atticle discusses the indications, pre-treatment preparation, treatment procedure and the rapeutic evaluation of pulp revascularization therapy.

Waveshape distortion of high frequency acoustic waves in gas media.

In molecular dynamics simulations of an acoustic domain excited by a sinusoidally oscillating plane acoustic source in the frequency range of hundreds of megahertz, the density and velocity perturbations adjacent to the source are observed to be non-sinusoidal in shape. This distortion in the shape of the waves is investigated using a number of simulations of frequencies in the hundred of megahertz range and velocities up to 0.50 Å/ps. The relative distortion of the wave shape is characterised by a developed nested trigonometric function. The distortion is shown to be a function of the Mach number of the acoustic source rather than the source velocity amplitude. Trends in the distortion with source amplitude and frequency indicate that distortion of the velocity and density are independent of frequency. It is shown that the density and velocity perturbation can be approximated for any sound source Mach number within the range examined using the parametrised developed equation. The developed approximation could be used to accurately simulate the influence of an oscillating plane using a stationary analytical source. This could be used to develop a hybrid molecular/continuum model that will allow lower frequency simulations. The improved understanding of the causes of the distorted high frequency waveshape could also improve the fidelity of parametric arrays.

[Clinical management of the intentional tooth replantation].

Intentional tooth replantation is the last resort for saving natural teeth in treatment of the endodontic diseases. In order to promote the utilization, standardize the operation and improve the success rate of this treatment, this review suggests the indication, discusses the key points of the surgical procedure, proposes the path of the diagnosis and the treatment protocol of the intentional replantation.

A Clinical Study on the Effect of Injection Sites on Efficacy of Anesthesia and Pulpal Blood Flow in Carious Teeth.

This randomized clinical trial evaluated the efficiency of maxillary infiltration anesthesia in carious teeth at two different injection sites and their impact on the laser Doppler recordings of pulpal blood flow (PBF) during a caries excavation procedure. The null hypothesis tested was that there are no differences in the efficiency of anesthesia and PBF reduction between maxillary infiltrations at the two injection sites. One hundred twenty patients were divided into three groups according to the degree of carious lesion of their maxillary left central incisors (moderate caries, deep caries, or no caries). Forty patients in each group randomly received infiltrations over the root apex of maxillary left central incisors (site X) or over the midpoint of the line connecting the root apexes of both maxillary left central and lateral incisors (site Y) using 0.9 mL 2% lidocaine with 1:100,000 adrenaline. Teeth were pulp tested at five-minute intervals after injection except for the period of cavity cutting, which was done 12 minutes after injection. The PBF changes after injection were monitored by laser Doppler flowmetry. The observation period in this study was 60 minutes. Success of anesthesia was defined as no or mild pain on cavity cutting by visual analog scale recordings. Deep caries group showed significantly higher baseline PBF ( p<0.05). All groups showed 100% success of anesthesia and similar duration time ( p>0.05). Subgroups that had the injection at site Y showed significantly less reduction of PBF ( p<0.05). Cavity-cutting procedures increased the amplitude of the PBF around the lowest value after injection. Independent of the cavity depth, carious anterior teeth anesthetized by infiltration further from the apex had significantly less reduction on the pulpal blood flow compared with teeth anesthetized by infiltration at the apex.

Refinement of generated fuzzy production rules by using a fuzzy neural network.

Fuzzy production rules (FPRs) have been used for years to capture and represent fuzzy, vague, imprecise and uncertain domain knowledge in many fuzzy systems. There have been a lot of researches on how to generate or obtain FPRs. There exist two methods to obtain FPRs. One is by painstakingly, repeatedly and time-consuming interviewing domain experts to extract the domain knowledge. The other is by using some machine learning techniques to generate and extract FPRs from some training samples. These extracted rules, however, are found to be nonoptimal and sometimes redundant. Furthermore, these generated rules suffer from the problem of low accuracy of classifying or recognizing unseen examples. The reasons for having these problems are 1) the FPRs generated are not powerful enough to represent the domain knowledge, 2) the techniques used to generate FPRs are pre-matured, ad-hoc or may not be suitable for the problem, and 3) further refinement of the extracted rules has not been done. In this paper we look into the solutions of the above problems by 1) enhancing the representation power of FPRs by including local and global weights, 2) developing a fuzzy neural network (FNN) with enhanced learning algorithm, and 3) using this FNN to refine the local and global weights of FPRs. By experimenting our method with some existing benchmark examples, the proposed method is found to have high accuracy in classifying unseen samples without increasing the number of the FPRs extracted and the time required to consult with domain experts is greatly reduced.

A new diphenyl ether from Phoma sp. strain, SHZK-2.

A new diphenyl ether methyl 2-(2-formyl-3-hydroxy-5-methylphenoxy)-5-hydroxy-3-methoxybenzoate (3), together with four known compounds, asterric acid (1), methyl asterrate (2), 9(Z),12(Z)-nonadecadienoic acid (4) and orsellinic acid (5), were isolated from the Phoma sp. strain SHZK-2, which was isolated from a polluted environment in southern China. The structures of these compounds were determined by spectroscopic methods. Cytotoxicities of compounds against HEPG2 cell and Raji cell lines were preliminarily evaluated by the MTT method.

Compare activities on regulating lipid-metabolism and reducing oxidative stress of diabetic rats of Tremella aurantialba broth's extract (TBE) with its mycelia polysaccharides (TMP).

Abnormal lipid-metabolism and elevated oxidative stress are the familiar complications of diabetic mellitus. Regulated lipid-metabolism and decreased oxidative stress have become the key indices to cure diabetic complications. The activities of broth extract (TBE) and mycelia polysaccharides (TMP) of Tremella aurantialba, which is one of the best-known multipurpose medicinal fungi in China, were studied using alloxan-induced diabetic rats. TBE contains saponins, while TMP contains polysaccharides. Both TBE and TMP could reduce the blood glucose levels of diabetic rats; TBE had stronger abilities to reduce the levels of total cholesterol and total triglyceride in serum, those of malondialdehyde, and enhance the activities of superoxide dismutase and glutathione reductase in different tissues of diabetic rats (P < 0.01). TBE had slightly stronger abilities to enhance the total antioxidant capability, catalase, and glutathione peroxidase in different tissues of diabetic rats, but no significant difference was found between TBE and TMP groups. All these results indicated that TBE was more capable of regulating lipid-metabolism and decreasing oxidative stress.

Temperature and length scale dependence of hydrophobic effects and their possible implications for protein folding.

The Lum-Chandler-Weeks theory of hydrophobicity [Lum, K., Chandler, D. & Weeks, J. D. (1999) J. Phys. Chem. 103, 4570-4577] is applied to treat the temperature dependence of hydrophobic solvation in water. The application illustrates how the temperature dependence for hydrophobic surfaces extending less than 1 nm differs significantly from that for surfaces extending more than 1 nm. The latter is the result of water depletion, a collective effect, that appears at length scales of 1 nm and larger. Because of the contrasting behaviors at small and large length scales, hydrophobicity by itself can explain the variable behavior of entropies of protein folding.

Analysis of cost and assessment of computerized patient record systems in Japan based on questionnaire survey.

PURPOSE: The purpose of this study was to clarify the implementation and maintenance costs of a computerized patient record (CPR) system by means of a questionnaire survey. Moreover, the benefits of CPR systems were evaluated to determine their contribution to enhancing the quality of medical care and hospital management. METHODS: Data were collected by a questionnaire survey mailed out to participants. RESULTS: The per-bed mean cost for implementation was 14,308 dollars (range: 3538-38,077 dollars). The mean annual maintenance cost for the CPR system was 457,615 dollars (range: 39,769-2,307,692 dollars). The multivariate analysis (Hayashi's Quantification Type I) revealed high partial correlation coefficients between implementation cost and the CPR system maker. In addition, the multiple correlation coefficient for four factors (CPR system maker, number of servers, institution type and implementation date) in predicting implementation cost was 0.798. Over 60% of respondents replied that their satisfaction with the CPR system was 'very high' or 'high.' Eighty-two percent of the hospitals responded positively that CPR systems improve the quality of medical care, and 70% felt that the systems help prevent medical errors. CONCLUSIONS: Our findings indicate that the maker of CPR system, number of servers, institution type and implementation date had a strong influence on per-bed implementation costs in that order. Finally, it was found that CPR systems were considered effective for hospital administration and medical examinations, based on the high assessments of the results of installing a CPR system.

[Adherence of the surface protein P(1) of Streptococcus mutans MT(6)R(Serotype C).].

In this study,the surface protein P(1) of Streptococcus mutans MT(6)R(Serotype C) was extracted from the culture supernants,purified by PAGE,identified by the standard antisera and labelled by with (131)I.The adherence of (131)I protein P(1)((131)I-P(1)) to the saliva-coated hydroxyaptite (S-HA) of the CF (caries-free,22,DFS=0) were studied.The adhesion of (131)I-P(1) to the S-HA promoted a greater extent than that to the HA treated with buffer and bovine serum albumin(P<0.01).This result suggested that protein P(1) may be one of the important adhesins of S.mutans.

Biocompatibility study of a biological tissue fixed with a naturally occurring crosslinking reagent.

A recognized disadvantage of the currently available chemical reagents used to fix bioprostheses is the potential toxic effects a recipient may be exposed to from residues. It is therefore desirable to provide a crosslinking reagent that is of low cytotoxicity and can form stable and biocompatible crosslinked products. To achieve this goal, a naturally occurring crosslinking reagent-genipin-was used by our group to fix biological tissues. Genipin can be obtained from its parent compound geniposide, which can be isolated from the fruits of Gardenia jasminoides ELLIS. In our previous feasibility study, it was found that the cytotoxicity of genipin is significantly lower than both glutaraldehyde and an epoxy compound. Additionally, it was shown that genipin can form stable crosslinked products. The present study further investigates the biocompatibility of a genipin-fixed porcine pericardium implanted subcutaneously in a growing rat model. The fresh, glutaraldehyde-, and epoxy-fixed counterparts were used as controls. It was noted that the inflammatory reaction of the genipin-fixed tissue was significantly less than its glutaraldehyde- and epoxy-fixed counterparts. Also, the genipin-fixed tissue has tensile strength and resistance against in vivo degradation comparable to the glutaraldehyde-fixed tissue. Additionally, the calcium content of the genipin-fixed tissue measured throughout the entire course of the study was minimal. Nevertheless, further study in calcification for the genipin-fixed tissue should be conducted in a blood-contact environment. The results obtained in this subcutaneous study indicate that genipin is a promising crosslinking reagent for biological tissue fixation. However, further durability testing in vitro and in vivo are needed to determine the relative functional merits of this new crosslinker.